Operative temperature sensing system

Abstract

An operative temperature sensing system including a first circuit including an air temperature sensor for providing a first signal which is a function of the air temperature within a room, a second circuit which provides a second signal which is a function of the mean radiant temperature within a room, and a third circuit for providing an output signal which is a function of the average of the first and second signals which in turn is a direct function of the operative temperature.

What is claimed is: 
     
       1. An operative temperature sensing system for providing an output which is a function of the operative temperature which is the uniform temperature of a radiantly black enclosure in which an occupant would exchange the same amount of heat by radiation plus convection as in the actual nonuniform environment comprising first temperature sensing means for generating a first signal having a value which is a function of the air temperature within said nonuniform environment, second temperature sensing means for generating a second signal having a value which is derived from a direct reading of and is a function of the mean radiant temperature in said nonuniform environment, and signal modifying circuit means for modifying said first and second signals for providing a third signal which has a value which is a function of the average of the sum of said first and second signals and thus is a function of the operative temperature within said nonuniform environment. 
     
     
       2. An operative temperature sensing system as set forth in claim 1 wherein said second temperature sensing mean comprises a responder which responds directly to mean radiant temperature and which is located within a chamber, a cover on said chamber for transmitting infrared waves therethrough from said nonuniform environment directly to said responder, and a reflector forming part of said chamber for reflecting infrared waves onto said responder. 
     
     
       3. An operative temperature sensing system as set forth in claim 1 wherein said signal modifying means include first signal modifying means for providing an output which is representative of half of said first signal, second circuit modifying means for providing an output which is representative of half of said second signal, and third circuit means for adding said outputs which are representative of said halves of said first and second signals. 
     
     
       4. An operative temperature sensing system as set forth in claim 3 wherein said second temperature sensing means comprises a responder which responds directly to mean radiant temperature and which is located within a chamber, a cover on said chamber for transmitting infrared waves therethrough from said nonuniform environment directly to said responder, and a reflector forming part of said chamber for reflecting infrared waves onto said responder. 
     
     
       5. An operative temperature sensing system as set forth in claim 3 wherein said first temperature sensing means is located adjacent to said second temperature sensing means. 
     
     
       6. An operative temperature sensing system as set forth in claim 1 wherein said signal modifying circuit means include an amplifier for adding said first and second signals. 
     
     
       7. An operative temperature sensing system as set forth in claim 6 wherein said second temperature sensing means comprises a responder which responds directly to mean radiant temperature and which is located within a chamber, a cover on said chamber for transmitting infrared waves therethrough from said nonuniform environment directly to said responder, and a reflector forming part of said chamber for reflecting infrared waves onto said responder. 
     
     
       8. An operative temperature sensing system as set forth in claim 1 including a set point reference signal generating means for developing a fourth signal that is a function of a desired set point temperature, and means responsive to said third signal and said fourth signal for developing an error signal that is a function of the difference therebetween. 
     
     
       9. An operative temperature sensing system as set forth in claim 8 wherein said second temperature sensing means comprises a responder which responds directly to mean radiant temperature and which is located within a chamber, to cover on said chamber for transmitting infrared waves therethrough from said nonuniform environment directly to said responder, and a reflector forming part of said chamber for reflecting infrared waves onto said responder. 
     
     
       10. An operative temperature sensing system as set forth in claim 1 wherein said second temperature sensing means comprises an infrared detector. 
     
     
       11. An operative temperature sensing system as set forth in claim 10 including set point reference signal generating means for developing a fourth signal which is a function of a desired set point temperature, and means responsive to said third signal and said fourth signal for developing an error signal which is a function of the difference therebetween. 
     
     
       12. An operative temperature sensing system as set forth in claim 11 wherein said infrared detector comprises a responder which senses mean radiant temperature and is located within a chamber, a cover on said chamber for transmitting infrared rays therethrough from said nonuniform environment directly to responder, and a reflector forming part of said chamber for reflecting infrared waves passing through said cover onto said responder. 
     
     
       13. A method of providing a signal which is the difference between a set point representing the desired operative temperature and the measured operative temperature within a nonuniform environment comprising the steps of measuring the air temperature within said nonuniform environment, producing a first signal from said measurement of said air temperature which is a function of said air temperature, measuring directly the mean radiant temperature within aid nonuniform environment, producing a second signal from said direct measurement of said mean radiant temperature which is a function of said mean radiant temperature, combining said first and second signals to produce a third signal which is a function of the average of the sum of said first and second signals and thus is a function of the measured operative temperature within said nonuniform environment, providing a fourth signal which is representative of a set point temperature which which is desired operative temperature within said nonuniform environment, and comparing said third and fourth signals to provide an error signal indicative of the difference therebetween.